> For the complete documentation index, see [llms.txt](https://docs.payments.thalescloud.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.payments.thalescloud.io/release-notes/sdk/september-2026/d1-sdk-4.5.0/asynchronous-apis-on-d1-sdk-4.5.0.md).

# Asynchronous APIs on D1 SDK 4.5.0

## Asynchronous APIs on D1 SDK 4.5.0

#### Overview

D1 SDK 4.5.0 introduces asynchronous API updates for iOS.

The updated APIs support Swift concurrency.

Use this guide to review the affected APIs and update your issuer application.

#### What changed

The previous API surface is deprecated in D1 SDK 4.5.0.

If your issuer application uses asynchronous calls, replace completion handlers with Swift concurrency APIs.

This page lists the APIs changed in 4.5.0.

#### Migrate to `digitalCardService`

{% stepper %}
{% step %}
**Review your current integration**

Identify the deprecated D1 SDK APIs used by your issuer application.

Focus on the APIs now exposed through `digitalCardService`.
{% endstep %}

{% step %}
**Initialize `digitalCardService`**

Initialize `digitalCardService` from `d1Task` before calling the updated APIs.
{% endstep %}

{% step %}
**Replace completion handlers**

Replace each completion-handler API with the corresponding `async throws` API.
{% endstep %}

{% step %}
**Validate the migrated flows**

Build and test your issuer application after the migration.

Validate the updated digital card flows.
{% endstep %}
{% endstepper %}

#### Update asynchronous handling

Use the Swift concurrency APIs if your issuer application uses Swift concurrency.

This makes asynchronous code easier to read and maintain.

`digitalCardService` calls now use `async throws` instead of completion handlers.

#### API changes in 4.5.0

Use this section to review the APIs changed in D1 SDK 4.5.0.

Initialize the service from `d1Task` before calling the APIs.

```swift
let digitalCardService = try d1Task.digitalCardService()
```

#### `digitalCardService`

**`activateDigitalCard(withDigitalCardID:)`**

Before:

```swift
public func activateDigitalCard(withDigitalCardID digitalCardID: String,
                                   completion: @escaping (D1Error?) -> Void)
```

Now:

```swift
public func activateDigitalCard(withDigitalCardID digitalCardID: String) async throws
```

**`activateDigitalCard(_:)`**

Before:

```swift
public func activateDigitalCard(_ cardID: String,
                                   completion: @escaping (D1Error?) -> Void)
```

Now:

```swift
public func activateDigitalCard(_ cardID: String) async throws
```

**`digitalCardList(_:)`**

Before:

```swift
public func digitalCardList(_ cardID: String,
                               completion: @escaping ([DigitalCard]?, D1Error?) -> Void)
```

Now:

```swift
public func digitalCardList(_ cardID: String) async throws -> [DigitalCard]
```

**`updateDigitalCard(_:digitalCard:action:)`**

Before:

```swift
public func updateDigitalCard(_ cardID: String,
                                 digitalCard: DigitalCard,
                                 action: CardAction,
                                 completion: @escaping (Bool, D1Error?) -> Void)
```

Now:

```swift
public func updateDigitalCard(_ cardID: String,
                                 digitalCard: DigitalCard,
                                 action: CardAction) async throws
```


---

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